1. Field of the Invention
The present invention relates to a net structure and methods for making the net structure and, more particularly, to a net structure made by slant weaving and methods for making the net structure.
2. Description of the Related Art
With reference to FIG. 1, a conventional net structure generally includes a plurality of side wires 91, a plurality of first metal wires 92, and a plurality of second metal wires 93. The side wires 91 together form a frame. The first and second metal wires 92 and 93 form a plurality of hexagonal meshes 94 inside the frame. Each first metal wire 92 includes a plurality of first extensions 95 and a plurality of first winding portions 96. The first extensions 95 and the first winding portions 96 are alternatively disposed. Furthermore, two adjacent first extensions 95 of the same first metal wire 92 extend in two different directions. As an example, the first extension portions 95′ and 95′″ extends leftward and downwards (see arrow α in FIG. 1), whereas the first extension portion 95″ extends rightwards and downwards (see arrow β in FIG. 1). Each second metal wire 93 includes a plurality of second extensions 97 and a plurality of second winding portions 98. The second extensions 97 and the second winding portions 98 are alternatively disposed. Similar to the first extension portions 95 of the first metal wires 92, two adjacent second extensions 97 of the same second metal wire 93 extend in two different directions.
By such an arrangement, a plurality of the first winding portions 96 of each of the first metal wires 92′ is intertwined with a plurality of the second winding portions 98 of two of the second metal wires 93′ and 93″. Thus, the first metal wires 92′ and the second metal wires 93′ extend in a direction perpendicular to the extending direction of the side wires 91. Furthermore, two sides of each hexagonal mesh 94 are twine portions 99 formed by one of the first winding portions 96 and one of the second winding portions 98. It is noted that each of the first metal wires 92′ and an adjacent second metal wire 93′ form a plurality of twine portions 99. The number of turns of each twine portion 99 of the conventional net structure is odd. In the conventional net structure shown in FIG. 1, the number of turns of each twine portion 99 is three.
However, since each first metal wire 92′ is merely intertwined with two second metal wires 93′, when any first metal wire 92′ breaks, an elongated hole A is formed between two second metal wires 93′ and has a size six times the size of a mesh 94, as shown in FIG. 2. The size of the hole A increases when the length of the broken first metal wire 92′ increases. In a case that the net structure is utilized as a net to hold stones, larger stones are liable to pass through the large hole A, failing to provide sufficient structural strength and failing to avoid landslide.
Thus, a need exists for an improved net structure with sufficient structural strength and for methods for making such a net structure.